Welcome to BetterBidding!
As this thread is nearly 4 years old and the OP may not see your question, i will provide some general information:
-all PRICELINE reservations (unless otherwise indicated) are booked for double occupancy, after that it is at the discretion of the hotel. Even if a bed choice of 2 Queen beds (or some other configuration that can accommodate 3/4 guests) is shown, the reservation is still technically for double occupancy, although i don't know of anyone who has yet had an issue showing up with 3/4 when the room is designed to accommodate this number of guests
With the above noted, a few TIPS to avoid any issues:
-i would not try this at an all-inclusive property or a location where wristbands are required to use certain features (ie- the water park at Atlantis in the Bahamas) as the types of situations almost always require an additional fee for more than double occupancy
-you can minimize the chances of any problems by only have 2 guests go to the check-in counter while the other(s) go begin to explore the hotel. Easier to do in a place like Las Vegas where the hotels are large, the check-in desk is not by the front door and only guests of the hotel are coming/going.... more difficult to do at a low star rated hotel in a rural area where the front desk is there to see everyone coming/going
-HOTWIRE allows searches for up to quad occupancy and guarantees 'sleeping accommodations' (often means 2 beds in the room but could include a pullout sofabed or rollaway brought into the room) for everyone included in the search, so that is another option if/when a 'bed choice' with 2 beds is not offered
-usually less of a risk if the 3rd/4th guests are children (the younger / smaller the better) than if the extra guests are adults
Lastly, there is often 'location specific' advice. For example, a high percentage of hotel rooms in Orlando are designed for families and the hotel is used to seeing groups of 3/4/more so the risk in a family-friendly place such as this is less vs. for example NYC where the opposite is true (rooms are usually smaller, often designed for a solo business traveler, etc)
If you'd like specific suggestions for your particular situation please feel free to start a NEW TOPIC with the parameters of your trip (location, dates, budget, number of guests, etc)
Please remember to return to BetterBidding and use the PRICELINE and HOTWIRE links on the board to begin your travel purchases... or thru our sister site MAPSandHOTELS.com for your regular rate purchases.